Summary:
========
Included in this advisory is an update for a newly discovered
vulnerability in Microsoft Internet Security and Acceleration
Server 2000. This vulnerability is rated Critical.

MS04-001 - Vulnerability in ISA Server H.323 Filter Could
Allow Remote Code Execution (816458)

- Affected Software:
- Microsoft Internet Security and
Acceleration Server 2000
- Microsoft Small Business Server 2000 (which
includes Microsoft Internet Security and
Acceleration Server 2000)
- Microsoft Small Business Server 2003 (which
includes Microsoft Internet Security and
Acceleration Server 2000)

- Impact: Remote Code Execution
- Version Number: 1.0

Update Availability:
===================
An update is available to fix this vulnerability.
For additional information, including Technical Details,
Workarounds, answers to Frequently Asked Questions, and Update
Deployment Information please read the Microsoft ISA Server
Security Bulletin Summary for January at:
http://www.microsoft.com/technet/security/bulletin/isajan04.asp

Acknowledgments:
================
Microsoft thanks the following for working with us to protect
customers:

- - The UK National Infrastructure Security Co-ordination Centre
(NISCC) (http://www.niscc.gov.uk) for reporting the issue described
in MS04-001.

Support:
========
Technical support is available from Microsoft Product Support
Services at 1-866-PC SAFETY (1-866-727-2338). There is no
charge for support calls associated with security patches.
International customers can get support from their local Microsoft
subsidiaries. Phone numbers for international support can be found
at: http://support.microsoft.com/common/international.aspx

Additional Resources:
=====================
* Microsoft has created a free monthly e-mail newsletter containing
valuable information to help you protect your network. This
newsletter provides practical security tips, topical security
guidance, useful resources and links, pointers to helpful
community resources, and a forum for you to provide feedback
and ask security-related questions.
You can sign up for the newsletter at:

http://www.microsoft.com/technet/security/secnews

* Join our Microsoft webcast for a live discussion of the technical
details of the January security bulletins and steps you can take
to protect your environment. Details can be found at:

http://msevents.microsoft.com/CUI/EventDetail.aspx?
EventID=1032241586&Culture=en-US

* Protect your PC: Microsoft has provided information on how you
can help protect your PC at the following locations:

http://www.microsoft.com/security/protect/

If you receive an e-mail that claims to be distributing a
Microsoft security patch, it is a hoax that may be distributing a
virus. Microsoft does not distribute security patches via e-mail.
You can learn more about Microsoft's software distribution
policies here:

http://www.microsoft.com/technet/security/policy/swdist.asp

Revisions:
==========
* V1.0 January 13, 2004: Bulletin Created.
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